Rfid tag authentication system

A radio frequency identification (RFID) tag authentication server, comprising:

• a storage unit having stored thereon an ID of an RFID tag, a first challenge value and a first response value corresponding to the first challenge value;
• a receiving unit configured to receive the first challenge value, time information of the RFID tag, an ID of an RFID reader and a first message authentication code from the RFID reader as tag identifiers;
• a tag identification unit configured to search the storage unit for the ID of the RFID tag and the first response value matched with the first challenge value;
• a MAC processing unit configured to generate a seventh message authentication code for the ID of the RFID reader, the ID of the RFID tag and time information of the RFID tag by using the first response value as a secret key;
• and
• a verification unit configured to determine whether the seventh message authentication code and the first message authentication code are coincident,
• wherein the first message authentication code is a message authentication code generated for the ID of the RFID reader, the ID of the RFID tag and the time information of the RFID tag by using the first response value as a secret key, and
• the RFID tag authentication server shares a message authentication code generation function, the ID of the RFID tag, the first challenge value and the first response value with the RFID tag.

The RFID tag authentication server of claim 8, further comprising:

• an encryption unit configured to encrypt preset data;
• and
• a transmitting unit configured to transmit the preset data to the RFID reader,
• wherein the MAC processing unit additionally generates a second message authentication code and a third message authentication code by using the first response value as a secret key,
• the encryption unit encrypts the second message authentication code and the second challenge value,
• the transmitting unit transmits the third message authentication code, time information of the RFID tag authentication server and the second message authentication code encrypted in the encryption unit to the RFID reader,
• the second message authentication code is a message authentication code for the time information of the RFID tag authentication server, the time information of the RFID tag, the ID of the RFID tag and the ID of the RFID reader, and
• the third message authentication code is a message authentication code for a second challenge value to be used next.

An authentication method of authenticating a radio frequency identification (RFID) tag by an RFID tag authentication server, the method comprising:

• generating a first challenge value;
• sharing a message authentication code generation function, an ID of the RFID tag, the first challenge value and a first response value corresponding to the first challenge value between the RFID tag authentication serve rand the RFID tag;
• receiving time information of the RFID tag, the first challenge value, an ID of an RFID reader and a first message authentication code from the RFID reader;
• generating a seventh message authentication code for the time information of the RFID tag, the ID of the RFID tag and the ID of the RFID reader by using the first response value as a secret key;
• and
• determining whether to authenticate the RFID tag based on whether the generated seventh message authentication code and the received message authentication code are coincident,
• wherein the first message authentication code is a message authentication code generated for the ID of the RFID reader, the ID of the RFID tag and the time information of the RFID tag by using the first response value as a secret value.